Hard Brake Pedal Diagnosis - Honda Accord 2019
A consistently hard brake pedal indicates a loss of power brake assist, likely due to a failed vacuum booster, vacuum leak, or faulty check valve. This significantly increases stopping distance and effort.
Diagnosis Details
Possible Causes
Failed brake booster (vacuum assist unit) - internal diaphragm leak or mechanical failure
Vacuum hose leak or disconnected hose from intake manifold to booster
Faulty brake booster check valve (one-way valve) allowing vacuum loss
Brake pedal pushrod adjustment out of spec (less common on modern vehicles)
Related OBD-II Codes
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What You Should Do
Do not drive the vehicle until repaired.
Check vacuum hose connections and the booster check valve for leaks or damage.
Test booster function by pumping brake pedal with engine off, then starting engine - pedal should drop slightly.
If not, replace booster.
Inspect for vacuum leaks using a vacuum gauge or smoke test.
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Disclaimer: This AI-generated diagnosis is for informational reference only. Always consult a qualified mechanic for an in-person inspection. AutOwner is not responsible for decisions made based on this information.
